SQLite Release 3.18.0 On 2017-03-30

• Added the PRAGMA optimize command
• The SQLite version identifier returned by the sqlite_source_id() SQL function and the sqlite3_sourceid() C API and found in the SQLITE_SOURCE_ID macro is now a 64-digit SHA3-256 hash instead of a 40-digit SHA1 hash.
• Added the json_patch() SQL function to the JSON1 extension.
• Enhance the LIKE optimization so that it works for arbitrary expressions on the left-hand side as long as the LIKE pattern on the right-hand side does not begin with a digit or minus sign.
• Added the sqlite3_set_last_insert_rowid() interface and use the new interface in the FTS3, FTS4, and FTS5 extensions to ensure that the sqlite3_last_insert_rowid() interface always returns reasonable values.
• Enhance PRAGMA integrity_check and PRAGMA quick_check so that they verify CHECK constraints.
• Enhance the query plans for joins to detect empty tables early and halt without doing unnecessary work.
• Enhance the sqlite3_mprintf() family of interfaces and the printf SQL function to put comma separators at the thousands marks for integers, if the "," format modifier is used in between the "%" and the "d" (example: "%,d").
• Added the -DSQLITE_MAX_MEMORY=N compile-time option.
• Added the .sha3sum dot-command and the .selftest dot-command to the command-line shell
• Begin enforcing SQLITE_LIMIT_VDBE_OP. This can be used, for example, to prevent excessively large prepared statements in systems that accept SQL queries from untrusted users.
• Various performance improvements.

  Bug Fixes:

• Ensure that indexed expressions with collating sequences are handled correctly. Fix for ticket eb703ba7b50c1a5.
• Fix a bug in the 'start of ...' modifiers for the date and time functions. Ticket 6097cb92745327a1
• Fix a potential segfault in complex recursive triggers, resulting from a bug in the OP_Once opcode introduced as part of a performance optimization in version 3.15.0. Ticket 06796225f59c057c
• In the RBU extension, add extra sync operations to avoid the possibility of corruption following a power failure.
• The sqlite3_trace_v2() output for nested SQL statements should always begin with a "--" comment marker.